Machine for digging up ground from below the surface



Dec. 24, 1929. MQJAEGER 1,740,923

MACHINE FOR DIGGING UP GROUND FROM BELOW THE SURFACE ile pr l 1929 2 Sheets-Sheet l Dec. 24, 1929. M. JAEGER 1,740,923

MACHINE FOR DIGGING UP GROUND FROM BELOW THE SURFACE Filed April 8, 1929 2 Sheets-Sheet 2 Max-faey Mg g m Patented Dec. 24, 1929 UNITED STATES PATENT OFFICE MAX JAEGER, OF WESSELBUREN, GERMANY, ASSIGNOR TO HEDWIG KRUEGER, OF WASHINGTON, DISTRICT OF COLUMBIA MACHINE FOR DIGGING UP GROUND FROM BELOW THE SURFACE Application filed April 8, 1929, Serial No. 353,608, and in Germany May 11, 1927.

My invention relates to machines for dig ging up ground from below the surface. It is an object of my invention to facilitate the feeding movement of the machine. To this end I provide two excavators in series and make the effective width of the leading excavator larger than that of the trailing excavator.

The machine is intended primarily for raising to the surface of the ground a stratum which is at a certain depth below the surface and to which is superposed a stratum which shall not be raised. The upper stratum which goes towaste, is handled by the leading excavator, the stratum below by the trailing excavator, which extends below the leading excavator so as to handle only the valuable stratum. Each excavator is provided with a casing of its own so as to convey the material from the two strata separately and to deposit it separately on the surface of the ground.

In apparatus of this type as heretofore der signed the feed was interfered with by the 0 ground in front of the first excavator. This drawback is eliminated by providing the larger effective width in the leading excavator. The width of the casing of the trailing excavator may also be smaller than the eflec- 3O tive width of the leading excavator, or the casing may be tapered toward the rear, so that it moves freely in the trench made by the leading excavator. It is also possible to reduce the width of the casing of the leading excavator as compared with its effective width, which may be effected by so designing the buckets of the leading excavator that their cutting edges 40 project on either side of the casing.

In the drawings affixed to this specification and forming part thereof a machine embodying my invention is illustrated diagrammatically by way of example.

In the drawings Fig. 1 is an elevation of my improved machine.

Fig. 2 is a rear end elevation of the machine, Fig. 3 is a section on the line 33 in Fig. 1,

Fig. 4 is an elevation of the lower end of the excavator set, drawn to a larger scale,

Fig. 5 is a plan view of one of the cutter guards, and

Fig. 6 is a partly sectional elevation thereof. 5

Referring to the drawings, 13 is the frame of a tractor or other suitable machine on which the casings 2 and 1 of the leading and trailing excavators are adapted to be rocked about trunnions 3 as a unit, so as to move them into their vertical or active position as shown or into substantially horizontal or inclined position, not shown, in which they are inactive. Any suitable means, not shown, may be provided for rocking the casings about their trunnions and obviously instead of trunnions about which the casings are rocked means may be provided for displacing them vertically or combined displacement and rocking movement may be imparted to the casings. Each excavator is equipped with the usual chains and buckets and sprockets. These means are old in the art and will not be described. 14 are the buckets of the leading, and 15 are those of the trailing excavator. The casings 1 and 2 are separated by a partition 11. A is the upper stratum which goes to waste and B is the lower stratum which is to be obtained. The leading excavator 2 handles only the upper stratum A and its casing is open at the front from the point 4, Fig. 1, as far as the point of delivery to a chute 6. The casing 1 of the trailing excavator extends to a certain depth into the stratum B and is open from its lowest point 7 to a point 7 which is still within the stratum B so that the buckets 15 can only handle the material from the stratum B and contamination from the stratum A is eliminated.

As will appear from Fig. 3, the edges of the buckets 14 are wider than the casing 2 of the leading excavator and the casing is slotted in front of the partition 11 at 16, Fig. 4, for the projecting edges of the buckets 14. With this arrangement the casing 2 will not jam in the trench made by its own buckets. The buckets 15 of the trailing excavator are narrower than those 14 of the leading excavator. As mentioned, the casing 1 may be narrower than the casing 2 but in the present instance the section of the casing 1 is made with a slight taper toward the rear, its width at the leading edge being equal to that of the casing 2.

The chute 6 at the rear of the leading excavator discharges the material from the stratum A into the trench made by the two excavators in the wake of the machine, and 12 is a chute at the rear of the trailing excavator which is shaped like a roof as shown in Fig. 2 and deflects the valuable material from the stratum B toward the sides of the trench.

In order to increase the delivery of the trailing excavator helical cutters of opposite pitch may be secured on the shaft- 17 of its lower sprocket as shown at 8 and 9 in Fig. 3. The helical cutters may be combined with guards 10 as shown in Figs. 5 and 6 which guards may be equipped with eyes 18 and 19 to be seated on the shaft 17 about which they are free to rock. A blade 20 is preferably formed at the rear end of the guard in order to hold it in proper position with respect to the helical cutters but obviously the guards might be fixed to the sides of the casing 1. The guards 1O facilitate the feeding of the soil loosened by the helical cutters to the buckets by preventing the passing of such soil rearwardly of the cutters. The blades hold the guards in position by resting on the bottom of the trench or upon the loosened soil therein, or by engagement with the walls of the trench. The pivotal connection between theguards 10 and the shaft 17 allows the blades 20 to pass over irregularities or obstructions in the trench.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described for obvious modifications will occur to a person skilled in the art.

In the claims affixed to this specification no selection of-any particular modification of the invention is intended to the exclusion of other modifications thereof and the right to subsequently make claim to any modification not covered by these claims is expressly reserved.

I claim 1. A machine for digging up ground from below the surface comprising a portable frame, two casings arranged in succession on said frame, and an excavator in each casing, the buckets of said leading excavator pro jecting beyond the sides of its casing.

2. A machine for digging up ground from below the surface comprising a portable frame, two casings arranged in succession on said frame, and an excavator in each casing, the casing of said trailing excavator being tapered toward the rear.

3. A machine for digging up ground from below the surface comprising a portable frame, two casings arranged in succession on said frame, an excavator in each casing, the casing of said leading excavator being open at the front, the casing of said trailing excavator extending beyond the lower end of the casing of said leading excavator and being open as far as the lower end of said casing, and buckets in said leading excavator which project beyond the sides of its casing, said casing having a slot for the projecting sides of said buckets.

4. A machine for digging up ground from below the surface comprising a portable frame, a leading and a trailing excavator on said frame, the efiective width of said leading excavator exceeding that of said trailing excavator, and helical cutters of opposite pitch at either side of said trailing excavator.

5. A machine for digging up ground from below the surface comprising a portable frame, a leading and a trailing excavator on said frame, the efiective width of said leading excavator exceeding that of said trailing excavator, helical cutters of opposite pitch at either side of said trailing excavator, and a guard at the rear of each cutter.

6. A machine for digging up ground from below the surface comprising a portable frame, a leading and a trailing excavator on said frame, the effective width of said leading excavator exceeding that of said trailing excavator, helical cutters of opposite pitch at either side of said trailing excavator, a guard at the rear of each cutter adapted to rock about the axis of said cutters, and a blade at the rear end of said guard.

7. A machine for digging up ground from below the surface comprising a portable frame, an excavator on said frame, a rotary cutter extending to the side of said excavator, a guard at the rear of said cutter adapted to rock about the axis of said cutter, and a guiding blade extending to the rear of said guard.

8. A machine for digging up ground from below the surface comprising a portable frame, an excavator on said frame, a helical cutter extending to the side of said excavator, a guard at the rear of said cutter adapted to rock about the axis of said cutter, and a guiding blade extending to the rear of said guard.

9. A machine for digging up ground from below the surface comprising a portable frame, an excavator on said frame, a' rotary shaft extending to the side of said excavator, a guard pivotally secured to said shaft and adapted to rock thereabout, and means to guide said guard.

10. A machine for digging up ground from below the surface comprising a portable frame, an excavator on said frame a rotary shaft extending to the side of saidexcavator, a helical cutter on said shaft, and a guard comprising an arcuate body portion arranged to the rear of the cutter, forwardly projecting ears on said body portion pivotally engaging the shaft whereby the guard is free to rock about the shaft, and a guiding blade extending rearwardly of said body portion of the guard.

11. A machine for digging up ground from below the surface comprising a portable frame, a leading and a trailing excavator on said frame, the effective width of said leading excavator exceeding that of said trailing excavator, a rotary shaftextending laterally of said trailing excavator, a helical cutter on said shaft, an arcuate guard arranged behind said helical cutter, forwardly projecting ears on said guard pivotally connected to said shaft whereby said guard is free to rock on said shaft, and a guiding blade extending rearwardly of said guard.

In testimony whereof I aflix my signature.

MAX JAEGER. 

